The present invention relates to a method of manufacturing a sintered ceramic body having a conductive layer thereon which is suitable for bonding with a metal member, especially a steel member.
A typical conventional method of bonding a sintered ceramic body to a metal member comprises applying an Mo-Mn paste or the like to a surface of the sintered ceramic body which is to be bonded, sintering the resultant structure in a reducing atmosphere to form a conductive layer which can be electroplated on this surface, electroplating nickel on the conductive layer and bonding an electroplated nickel layer to the metal member by brazing.
This method is very effective when the ceramic body comprises an oxide series sintered body such as alumina, but is not suitable when an non-oxide series sintered body such as silicon nitride is used. In particular, when a metal member comprises steel, direct bonding through diffusion cannot be substantially achieved at low temperature. When the steel member is bonded at high temperature, properties of the steel member is greatly degraded, resulting in inconvenience.
Since a non-oxide series sintered ceramic body such as a silicon nitride sintered body has good wearing and high-temperature properties, this sintered body shows promise for application in automobile parts and gas turbine parts. A strong demand has arisen for establishing a technique for bonding such a non-oxide series ceramic body with a metal member, especially a steel member.